login
a(n) = n*tau(a(n-1)) + 1 = n*A000005(a(n-1)) + 1, a(0) = 1.
2

%I #13 May 25 2021 10:30:20

%S 1,2,5,7,9,16,31,15,33,37,21,45,73,27,57,61,33,69,73,39,81,106,89,47,

%T 49,76,157,55,113,59,61,63,193,67,69,141,145,149,77,157,81,206,169,

%U 130,353,91,185,189,385,393,201,205,209,213,217,221,225,514,233,119,241,123,249

%N a(n) = n*tau(a(n-1)) + 1 = n*A000005(a(n-1)) + 1, a(0) = 1.

%H Harvey P. Dale, <a href="/A083272/b083272.txt">Table of n, a(n) for n = 0..1000</a>

%t h[x_] := x*DivisorSigma[0, h[x-1]]]+1 Table[h[w], {w, 1, 100}]

%t nxt[{n_,a_}]:={n+1, (n+1)DivisorSigma[0,a]+1}; NestList[nxt,{0,1},70][[All,2]] (* _Harvey P. Dale_, Feb 06 2020 *)

%Y Cf. A000005, A083271.

%K easy,nonn

%O 0,2

%A _Labos Elemer_, May 14 2003